Male Swollen Breast Hi, Why Does My Dog Developed Milk In Here Breast Even If She Have No Contact With A Male Dog?

Hi, why does my dog developed milk in here breast even if she have no contact with a male dog? - male swollen breast

Ashley My dog is a mongrel and Chiwawa dacshund, and only after the period, swollen breasts, and great lap and milk production. She has four years and when that happens, it is very difficult when you spill milk and walk on the couch and the floor of his chest.
She and our other dog (Britney still) never heard of our area surrounded by concrete.